Publications
USGS research activities relevant to Alaska have yielded more than 9400 historical publications. This page features some of the most recent newsworthy research findings.
Filter Total Items: 3096
Glaciological and marine geological controls on terminus dynamics of Hubbard Glacier, southeast Alaska Glaciological and marine geological controls on terminus dynamics of Hubbard Glacier, southeast Alaska
Hubbard Glacier, located in southeast Alaska, is the world's largest non-polar tidewater glacier. It has been steadily advancing since it was first mapped in 1895; occasionally, the advance creates an ice or sediment dam that blocks a tributary fjord (Russell Fiord). The sustained advance raises the probability of long-term closure in the near-future, which will strongly impact the...
Authors
Leigh A. Stearns, Gordon S. Hamilton, C. J. van der Veen, D. C. Finnegan, Shad O’Neel, J. B. Scheick, D. E. Lawson
Icefield-to-ocean linkages across the northern Pacific coastal temperate rainforest ecosystem Icefield-to-ocean linkages across the northern Pacific coastal temperate rainforest ecosystem
Rates of glacier mass loss in the northern Pacific coastal temperate rainforest (PCTR) are among the highest on Earth, and changes in glacier volume and extent will affect the flow regime and chemistry of coastal rivers, as well as the nearshore marine ecosystem of the Gulf of Alaska. Here we synthesize physical, chemical and biological linkages that characterize the northern PCTR...
Authors
Shad O’Neel, Eran Hood, Allison L. Bidlack, Sean W. Fleming, Mayumi L. Arimitsu, Anthony Arendt, Evan W. Burgess, Christopher J. Sergeant, Anne E. Beaudreau, Kristin Timm, Gregory D. Hayward, Joel H. Reynolds, Sanjay Pyare
Focused exhumation along megathrust splay faults in Prince William Sound, Alaska Focused exhumation along megathrust splay faults in Prince William Sound, Alaska
Megathrust splay faults are a common feature of accretionary prisms and can be important for generating tsunamis during some subduction zone earthquakes. Here we provide new evidence from Alaska that megathrust splay faults have been conduits for focused exhumation in the last 5 Ma. In most of central Prince William Sound, published and new low-temperature thermochronology data indicate...
Authors
Peter J. Haeussler, Phillip A Armstrong, Lee M Liberty, Kelly M Ferguson, Shaun P Finn, Jeannette C Arkle, Thomas L. Pratt
Species richness and distributions of boreal waterbirds in relation to nesting and brood-rearing habitats Species richness and distributions of boreal waterbirds in relation to nesting and brood-rearing habitats
Identification of ecological factors that drive animal distributions allows us to understand why distributions vary temporally and spatially, and to develop models to predict future changes to populations–vital tools for effective wildlife management and conservation. For waterbird broods in the boreal forest, distributions are likely driven by factors affecting quality of nesting and...
Authors
Tyler L. Lewis, Mark S. Lindberg, Joel A. Schmutz, Mark R. Bertram, Adam J. Dubour
Projected changes in wildlife habitats in Arctic natural areas of northwest Alaska Projected changes in wildlife habitats in Arctic natural areas of northwest Alaska
We project the effects of transitional changes among 60 vegetation and other land cover types (“ecotypes”) in northwest Alaska over the 21st century on habitats of 162 bird and 39 mammal species known or expected to occur regularly in the region. This analysis, encompassing a broad suite of arctic and boreal wildlife species, entailed building wildlife-habitat matrices denoting levels of...
Authors
Bruce G. Marcot, M. Torre Jorgenson, James P. Lawler, Colleen M. Handel, Anthony R. DeGange
Ecology and conservation of North American sea ducks Ecology and conservation of North American sea ducks
The past decade has seen a huge increase in the interest and attention directed toward sea ducks, the Mergini tribe. This has been inspired, in large part, by the conservation concerns associated with numerical declines in several sea duck species and populations, as well as a growing appreciation for their interesting ecological attributes. Reflecting the considerable research recently...
Identifying a reliable blubber measurement site to assess body condition in a marine mammal with topographically variable blubber, the Pacific walrus Identifying a reliable blubber measurement site to assess body condition in a marine mammal with topographically variable blubber, the Pacific walrus
Pacific walruses may be unable to meet caloric requirements in the changing Arctic ecosystem, which could affect body condition and have population-level consequences. Body condition has historically been monitored by measuring blubber thickness over the xiphoid process (sternum). This may be an unreliable condition index because blubber at other sites along the body may be...
Authors
Shawn R. Noren, Mark S. Udevitz, Lisa Triggs, Jessa Paschke, Lisa Oland, Chadwick V. Jay
Phylogenetics, phylogeography and population genetics of North American sea ducks (tribe: Mergini) Phylogenetics, phylogeography and population genetics of North American sea ducks (tribe: Mergini)
Many environments occupied by North American sea ducks are remote and difficult to access, and as a result, detailed information about life history characteristics that drive population dynamics within and across species is limited. Nevertheless, progress on this front during the past several decades has benefited by the application of genetic technologies, and for several species, these
Authors
Sandra L. Talbot, Sarah A. Sonsthagen, John M. Pearce, Kim T. Scribner
Habitats of North American sea ducks. Habitats of North American sea ducks.
Breeding, molting, fall and spring staging, and wintering habitats of the sea duck tribe Mergini are described based on geographic locations and distribution in North America, geomorphology, vegetation and soil types, and fresh water and marine characteristics. The dynamics of habitats are discussed in light of natural and anthropogenic events that shape areas important to sea ducks...
Authors
Dirk V. Derksen, Margaret R. Petersen, Jean-Pierre L. Savard
Variation in migration strategies of North American sea ducks Variation in migration strategies of North American sea ducks
Migration exerts strong effects on population dynamics, so consideration of migration as a driver of population change is an important area of inquiry. Sea ducks (Mergini) exemplify the wide range in types of migration strategies, which become more variable with the addition of a third migration to distinct molting areas. We discuss the three migrations, summer, fall, and molt, and...
Authors
Margaret R. Petersen, Jean-Pierre L. Savard
Conclusions, synthesis, and future directions: understanding sources of population change Conclusions, synthesis, and future directions: understanding sources of population change
The material in this volume reflects the burgeoning interest in sea ducks, both as study species with compelling and unique ecological attributes and as taxa of conservation concern. In this review, we provide perspective on the current state of sea duck knowledge by highlighting key findings in the preceding chapters that are of particular value for understanding or influencing...
Authors
Daniel Esler, Paul L. Flint, Dirk V. Derksen, Jean-Pierre L. Savard, John M. Eadie
Remigial molt of sea ducks Remigial molt of sea ducks
Molt is a dynamic process occurring throughout much of the year in waterfowl. The molt of flight feathers by waterfowl, especially sea ducks, however, occurs over a compressed period of time and in spcific areas used each year. We provide an overview of the flight feather molt of sea ducks. We focus on the need to molt and why, the timing and duration of flight feather mot, and the...
Authors
Margaret R. Petersen, Jean-Pierre L. Savard